﻿<!DOCTYPE html>
<html lang="en">
    <head>
        <title>情人节快乐</title>
        <meta charset="utf-8">
        <meta name="viewport" content="width=device-width, user-scalable=no, minimum-scale=1.0, maximum-scale=1.0">
        <style>
            body {
                font-family: Monospace;
                background-color: #f0f0f0;
                margin: 0px;
                overflow: hidden;
            }
        </style>
    </head>
    <body>
        <script src="js/nb.js"></script>
        <script src="js/Projector.js"></script>
        <script src="js/CanvasRenderer.js"></script>
        <script src="js/tween.min.js"></script>
        <script src="js/Sparks.js"></script>
        <!-- load the font file from canvas-text -->
        <script src="js/helvetiker_regular.typeface.js"></script>
        <script>
            var container;
            var camera, scene, renderer;
            var group, text, plane;
            var targetRotation = 0;
            var targetRotationOnMouseDown = 0;
            var mouseX = 0;
            var mouseXOnMouseDown = 0;
            var windowHalfX = window.innerWidth / 2;
            var windowHalfY = window.innerHeight / 2;
            var heartShape, particleCloud, sparksEmitter, emitterPos;
            var _rotation = 0;
            var timeOnShapePath = 0;
            init();
            animate();
            function init() {
                container = document.createElement('div');
                document.body.appendChild(container);
                //相机
                camera = new THREE.PerspectiveCamera(50, window.innerWidth / window.innerHeight, 1, 1000);
                camera.position.set(0, 150, 800);
                //场景
                scene = new THREE.Scene();
                group = new THREE.Group();
                scene.add(group);
                // Get text from hash
                var string = "I Love You";
                var hash = document.location.hash.substr(1);
                if (hash.length !== 0) {
                    string = hash;
                }
                var text3d = new THREE.TextGeometry(string, {
                    size: 70,
                    height: 20,
                    curveSegments: 2,
                    font: "helvetiker"
                });
                text3d.computeBoundingBox();
                var centerOffset = -0.5 * (text3d.boundingBox.max.x - text3d.boundingBox.min.x);
                var textMaterial = new THREE.MeshBasicMaterial({color: Math.random() * 0xffffff, overdraw: 0.5});
                text = new THREE.Mesh(text3d, textMaterial);
                // Potentially, we can extract the vertices or faces of the text to generate particles too.
                // Geo > Vertices > Position
                text.position.x = centerOffset;
                text.position.y = 100;
                text.position.z = 0;
                text.rotation.x = 0;
                text.rotation.y = Math.PI * 2;
                group.add(text);
                particleCloud = new THREE.Object3D(); // Just a group
                particleCloud.y = 800;
                group.add(particleCloud);
                // Create Particle Systems
                // Heart
                var x = 0, y = 0;
                heartShape = new THREE.Shape();
                heartShape.moveTo(x + 25, y + 25);
                heartShape.bezierCurveTo(x + 25, y + 25, x + 20, y, x, y);
                heartShape.bezierCurveTo(x - 30, y, x - 30, y + 35, x - 30, y + 35);
                heartShape.bezierCurveTo(x - 30, y + 55, x - 10, y + 77, x + 25, y + 95);
                heartShape.bezierCurveTo(x + 60, y + 77, x + 80, y + 55, x + 80, y + 35);
                heartShape.bezierCurveTo(x + 80, y + 35, x + 80, y, x + 50, y);
                heartShape.bezierCurveTo(x + 35, y, x + 25, y + 25, x + 25, y + 25);
                var hue = 0;
                var hearts = function(context) {
                    context.globalAlpha = 0.5;
                    var x = 0, y = 0;
                    context.scale(0.05, -0.05); // Scale so canvas render can redraw within bounds
                    context.beginPath();
                    // From http://blog.burlock.org/html5/130-paths
                    context.bezierCurveTo(x + 2.5, y + 2.5, x + 2.0, y, x, y);
                    context.bezierCurveTo(x - 3.0, y, x - 3.0, y + 3.5, x - 3.0, y + 3.5);
                    context.bezierCurveTo(x - 3.0, y + 5.5, x - 1.0, y + 7.7, x + 2.5, y + 9.5);
                    context.bezierCurveTo(x + 6.0, y + 7.7, x + 8.0, y + 5.5, x + 8.0, y + 3.5);
                    context.bezierCurveTo(x + 8.0, y + 3.5, x + 8.0, y, x + 5.0, y);
                    context.bezierCurveTo(x + 3.5, y, x + 2.5, y + 2.5, x + 2.5, y + 2.5);
                    context.fill();
                    context.lineWidth = 0.5; //0.05
                    context.stroke();
                }
                var setTargetParticle = function() {
                    var material = new THREE.SpriteCanvasMaterial({
                        program: hearts
                    });
                    material.color.setHSL(hue, 1, 0.75);
                    hue += 0.001;
                    if (hue > 1)
                        hue -= 1;
                    particle = new THREE.Sprite(material);
                    particle.scale.x = particle.scale.y = Math.random() * 40 + 40;
                    particleCloud.add(particle);
                    return particle;
                };
                var onParticleCreated = function(p) {
                    p.target.position.copy(p.position);
                };
                var onParticleDead = function(particle) {
                    particle.target.visible = false;
                    particleCloud.remove(particle.target);
                };
                sparksEmitter = new SPARKS.Emitter(new SPARKS.SteadyCounter(160));

                emitterpos = new THREE.Vector3();

                sparksEmitter.addInitializer(new SPARKS.Position(new SPARKS.PointZone(emitterpos)));
                sparksEmitter.addInitializer(new SPARKS.Lifetime(0, 2));
                sparksEmitter.addInitializer(new SPARKS.Target(null, setTargetParticle));

                sparksEmitter.addInitializer(new SPARKS.Velocity(new SPARKS.PointZone(new THREE.Vector3(0, -50, 10))));

                // TOTRY Set velocity to move away from centroid

                sparksEmitter.addAction(new SPARKS.Age());
                //sparksEmitter.addAction(new SPARKS.Accelerate(0.2));
                sparksEmitter.addAction(new SPARKS.Move());
                sparksEmitter.addAction(new SPARKS.RandomDrift(50, 50, 2000));

                sparksEmitter.addCallback("created", onParticleCreated);
                sparksEmitter.addCallback("dead", onParticleDead);
                sparksEmitter.addCallback("updated", function(particle) {
                    particle.target.position.copy(particle.position);
                });
                sparksEmitter.start();
                // End Particles
                renderer = new THREE.CanvasRenderer();
                renderer.setClearColor(0xf0f0f0);
                renderer.setPixelRatio(window.devicePixelRatio);
                renderer.setSize(window.innerWidth, window.innerHeight);
                container.appendChild(renderer.domElement);
                document.addEventListener('mousedown', onDocumentMouseDown, false);
                document.addEventListener('touchstart', onDocumentTouchStart, false);
                document.addEventListener('touchmove', onDocumentTouchMove, false);
                //
                window.addEventListener('resize', onWindowResize, false);
            }
            function onWindowResize() {
                windowHalfX = window.innerWidth / 2;
                windowHalfY = window.innerHeight / 2;
                camera.aspect = window.innerWidth / window.innerHeight;
                camera.updateProjectionMatrix();
                renderer.setSize(window.innerWidth, window.innerHeight);
            }
            //
            document.addEventListener('mousemove', onDocumentMouseMove, false);
            function onDocumentMouseDown(event) {
                event.preventDefault();
                mouseXOnMouseDown = event.clientX - windowHalfX;
                targetRotationOnMouseDown = targetRotation;
                if (sparksEmitter.isRunning()) {
                    sparksEmitter.stop();
                } else {
                    sparksEmitter.start();
                }
            }
            function onDocumentMouseMove(event) {
                mouseX = event.clientX - windowHalfX;
                targetRotation = targetRotationOnMouseDown + (mouseX - mouseXOnMouseDown) * 0.02;
            }
            function onDocumentTouchStart(event) {
                if (event.touches.length == 1) {
                    event.preventDefault();
                    mouseXOnMouseDown = event.touches[ 0 ].pageX - windowHalfX;
                    targetRotationOnMouseDown = targetRotation;
                }
            }
            function onDocumentTouchMove(event) {
                if (event.touches.length == 1) {
                    event.preventDefault();
                    mouseX = event.touches[ 0 ].pageX - windowHalfX;
                    targetRotation = targetRotationOnMouseDown + (mouseX - mouseXOnMouseDown) * 0.05;
                }
            }
            //
            function animate() {//更新场景
                requestAnimationFrame(animate);
                render();
            }
            function render() {
                timeOnShapePath += 0.0337;
                if (timeOnShapePath > 1)
                    timeOnShapePath -= 1;
                // TODO Create a PointOnShape Action/Zone in the particle engine
                var pointOnShape = heartShape.getPointAt(timeOnShapePath);
                emitterpos.x = pointOnShape.x * 5 - 100;
                emitterpos.y = -pointOnShape.y * 5 + 400;
                // Pretty cool effect if you enable this
                // particleCloud.rotation.y += 0.05;
                group.rotation.y += (targetRotation - group.rotation.y) * 0.05;
                renderer.render(scene, camera);
            }
        </script>
    </body>
</html>
